**6. Conclusions**

Facing energy demand challenges to ensure sustainable economic growth, especially the exhaustion of fossil fuels, environmental pollution, and climate change. Incentive policies to take advantage of renewable energy supply opportunities in Vietnam. This approach to taking advantage of this new energy source not only contributes to timely supply of the energy needs of the society but also helps to save electricity and reduce environmental pollution.

However, when considering investing in solar power plants, decision makers must consider many qualitative and quantitative factors including economic, technological, site characteristics, environmental and social factors. Therefore, this problem is tackled as a Multi-Criteria Decision Making (MCDM) problem that requires that both quantitative and qualitative information are considered. This paper presented an integrated approach for site of solar plants by data envelopment analysis (DEA) and Fuzzy Analytical Network Process (FANP). Furthermore, this integrated approach, incorporating the most relevant parameters of solar plants, is introduced.

The contributions of this research include a fuzzy multicriteria decision-making (F-MCDM) approach for solar power plant site selection in Vietnam. This research also utilizes the evolution of a new approach that is flexible and practical for the decision-maker and provides useful guidelines for solar power plant location selection in many countries around the world.

For further studies regarding this topic, the study can be expanded to other MCDM approaches such as VIKOR, ELECTRE I, ELECTRE III.

**Author Contributions:** Conceptualization, C.-N.W., T.P.H., V.T.N. and S.T.H.; Data curation, V.T.H.V., T.P.H. and V.T.N.; Formal analysis, C.-N.W., V.T.H.V., T.P.H., V.T.N. and S.T.H.; Funding acquisition, C.-N.W. and V.T.H.V.; Investigation, C.-N.W., T.P.H., V.T.N. and S.T.H.; Methodology, C.-N.W., V.T.H.V., T.P.H. and V.T.N.; Project administration, V.T.H.V., T.P.H. and V.T.N.; Resources, V.T.N.; Visualization, T.P.H. and S.T.H.; Writing—original draft, V.T.H.V., T.P.H.,V.T.N. and S.T.H.; Writing—review and editing, C.-N.W., V.T.H.V. and V.T.N. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
